Tech Talk - Canon CN-E & Zeiss Compact Primes

Canon CN-E & Zeiss Compact Primes

A introductory look at the Canon Cinema Primes and the new Zeiss Superspeeds

We live in an age where professional TV and Cinema cameras are producing ever better performance at an ever decreasing cost and any cameras performance is defined by the glass up front. Cinema style lenses are highly specialised and expensive but the boom in relatively cheap large sensor digital cinema cameras has also changed the world of lenses.

Camera manufacturers are now building cameras capable of using photographic still lenses. Many have seen their optical quality but bemoaned their poor mechanics. Zeiss was first off the mark creating their Compact Prime CP.2 family optically based on the ZF/ZE family of stills lenses. The Super speeds we tested are a subset of the CP.2 family and as I understand it use the same glass as the equivalent CP.2s but are not aperture limited. Now Canon have released their EF Cinema Prime CN family as well which I assume is based their EF L series. These already proven optical designs partly allow for the low cost but the downside is the available focal lengths is determined by what already exists. We may never see a 18mm T1.5 from either Zeiss or Canon in these sets.

The ACS Technical Committee came to the following conclusions:

We used the Zeiss Ultraprimes as a benchmark although they are not as fast as the new boys on the block they are well known quality workhorse glass. I would also like to qualify that lens preference is personal and can be based on many parameters. For a more detailed look check out the bottom of this page for the link to the High res stills from the test. (Please ignore the yellow line through some of the test charts as I used the shutter instead of ND filters causing a sync issue with the fluorescent backlight.) Also check out the link for the ACS Vimeo site for a video chat about the results. ??

Brief summary

Pros

CP.2 and Canon CN lenses are one third to a quarter the cost of equivalent Cinema primes.

Fast glass with the Canons pushing into new territory for cinema glass with T1.3

Optical quality extremely high although top end glass will still probably technically outperform wide open.

The CP.2 and Canon CN lenses cover a 24mmx36mm sensor so are likely to cover any Digital Cinema camera sensor in the future.

The Canon glass is presently missing the 35mm focal length which is near fatal and while a 14mm F2.8 and a 135mmF2 have been announced there are many focal lengths missing. Zeiss has a good range in the CP.2 line but the F Stop varies from T3.6 to T1.5!

Both Canon and Zeiss do know how to build lenses but the long term mechanical reliability is an unkown.

The Canon CN lenses are EF mount only so unless you are a Red, Phantom or Canon camera user they are a non starter.

In the snobbish world of lenses neither brand carries the cache of their established competitors.

24mm Lenses

There is only the Canon T1.5 as there is no "24mm Superspeed" although there is a 24mmm CP.2 at T 2.1.

At T1.9 the 24mm Canon shows a much higher resolving power than the equivalent Ultraprime at T1.9 even at T1.5 the Canon still outperforms. The Ultraprime 24mm is also showing its S35 design limitations and the frame area beyond 4K into the 5K is very soft.Vignetting on the 24mm is less than the Ultraprime. The Canon 24mm is a great lens and I personally like my wider lenses sharp.

35mm Lenses

Again only two contenders as Canon does not have a 35mm focal length. The Ultraprime at T1.9 does outperform the Cp.2 Superspeed at T1.5. The Superspeed may have marginally more res wide open the flare/contrast issue wide open lets it down. At T5.6 the Superspeed edges ahead of the Ultraprime

50mm Lenses

First focal length for all three contenders. Wide open the Ultraprime is the winner followed by the Canon then the Superspeed but the Canon is T1.3 at wide open and Superspeed is T1.5. while tthe bencchmark Ulltrraprimee is T1.9. At T5.6 its a very close race but my call would go the Superspeed then the Ultraprime and Canon.

85mm Lenses

Wide open the Ultraprime is T1.9, Canon is T1.3 and Superspeed T1.5Resolution looks very similar between the Ultraprime and Superspeed with the 85mm Canon last. At T5.6 the Canon is still marginally behind the others in terms of resolution although it edges ahead in the corners.

Colour rendition is probably best judged from the supplied test files on The ACS Website. To my eye the colour is very similar between the two Zeiss glass families with the Canon being a hairline warmer? We had a brief look at flare using a Dedo lamp in shot on our test model. Results were similiar but it certainly was not an exhaustive test.

We tested breathing on the lenses and they all performed well in this regard. Without pulling the lenses apart they all has an excellent mechanical feel. I understand that the owner of the Superspeeds initially rejected his first set as the focus rotation had some "lumpiness" but as you would expect from Zeiss they were promptly replaced.

A further note is both Canon and Superspeeds have a softer lower contrast look wide open. The ACS Technical Committee do not see this as a disadvantage. The shallow DOF and creamier look is a valuable tool and can work very well on faces and portraits. The extra speed of the 50mm and 85mm Canon at T1.3 really helps here.

Check out the video review at the ACS Vimeo channel https://vimeo.com/55985070

With thanks to all those from the ACS Technical Committee; David Wakeley ACS, Franc Biffone, Dan Freene ACS and Lemac Rentals who participated in this round of testing.